[PATCH 13/27] HID: wacom: leds: dynamically allocate LED groups

Benjamin Tissoires
2016-07-05T14:40:08Z

We need to add an action to ensure wacom->led.groups is null when
wacom_led_control() gets called after the resources has been freed.

This also prevents to send a LED command when there is no support
from the device.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
---
drivers/hid/wacom.h | 8 +++--
drivers/hid/wacom_sys.c | 85 +++++++++++++++++++++++++++++++++++++++++--------
drivers/hid/wacom_wac.c | 2 +-
3 files changed, 78 insertions(+), 17 deletions(-)

diff --git a/drivers/hid/wacom.h b/drivers/hid/wacom.h
index bcfeb51..8ac1eb8 100644
--- a/drivers/hid/wacom.h
+++ b/drivers/hid/wacom.h
@@ -110,6 +110,10 @@ enum wacom_worker {
WACOM_WORKER_BATTERY,
};

+struct wacom_group_leds {
+ u8 select; /* status led selector (0..3) */
+};
+
struct wacom {
struct usb_device *usbdev;
struct usb_interface *intf;
@@ -118,8 +122,8 @@ struct wacom {
struct mutex lock;
struct work_struct wireless_work;
struct work_struct battery_work;
- struct wacom_led {
- u8 select[5]; /* status led selector (0..3) */
+ struct wacom_leds {
+ struct wacom_group_leds *groups;
u8 llv; /* status led brightness no button (1..127) */
u8 hlv; /* status led brightness button pressed (1..127) */
u8 img_lum; /* OLED matrix display brightness */
diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index d0f5764..4d4c737 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -647,6 +647,9 @@ static int wacom_led_control(struct wacom *wacom)
unsigned char report_id = WAC_CMD_LED_CONTROL;
int buf_size = 9;

+ if (!wacom->led.groups)
+ return -ENOTSUPP;
+
if (wacom->wacom_wac.pid) { /* wireless connected */
report_id = WAC_CMD_WL_LED_CONTROL;
buf_size = 13;
@@ -662,7 +665,7 @@ static int wacom_led_control(struct wacom *wacom)
* one of four values:
* 0 = Low; 1 = Medium; 2 = High; 3 = Off
*/
- int ring_led = wacom->led.select[0] & 0x03;
+ int ring_led = wacom->led.groups[0].select & 0x03;
int ring_lum = (((wacom->led.llv & 0x60) >> 5) - 1) & 0x03;
int crop_lum = 0;
unsigned char led_bits = (crop_lum << 4) | (ring_lum << 2) | (ring_led);
@@ -677,11 +680,11 @@ static int wacom_led_control(struct wacom *wacom)
buf[1] = led_bits;
}
else {
- int led = wacom->led.select[0] | 0x4;
+ int led = wacom->led.groups[0].select | 0x4;

if (wacom->wacom_wac.features.type == WACOM_21UX2 ||
wacom->wacom_wac.features.type == WACOM_24HD)
- led |= (wacom->led.select[1] << 4) | 0x40;
+ led |= (wacom->led.groups[1].select << 4) | 0x40;

buf[0] = report_id;
buf[1] = led;
@@ -753,7 +756,7 @@ static ssize_t wacom_led_select_store(struct device *dev, int set_id,

mutex_lock(&wacom->lock);

- wacom->led.select[set_id] = id & 0x3;
+ wacom->led.groups[set_id].select = id & 0x3;
err = wacom_led_control(wacom);

mutex_unlock(&wacom->lock);
@@ -773,7 +776,7 @@ static ssize_t wacom_led##SET_ID##_select_show(struct device *dev, \
struct hid_device *hdev = to_hid_device(dev);\
struct wacom *wacom = hid_get_drvdata(hdev); \
return scnprintf(buf, PAGE_SIZE, "%d\n", \
- wacom->led.select[SET_ID]); \
+ wacom->led.groups[SET_ID].select); \
} \
static DEVICE_ATTR(status_led##SET_ID##_select, DEV_ATTR_RW_PERM, \
wacom_led##SET_ID##_select_show, \
@@ -955,6 +958,35 @@ static int wacom_devm_sysfs_create_group(struct wacom *wacom,
return 0;
}

+static void wacom_led_groups_release(void *data)
+{
+ struct wacom *wacom = data;
+
+ wacom->led.groups = NULL;
+}
+
+static int wacom_led_groups_allocate(struct wacom *wacom, int count)
+{
+ struct wacom_group_leds *groups;
+ int error;
+
+ groups = devm_kzalloc(&wacom->hdev->dev,
+ sizeof(struct wacom_group_leds) * count,
+ GFP_KERNEL);
+ if (!groups)
+ return -ENOMEM;
+
+ error = devm_add_action_or_reset(&wacom->hdev->dev,
+ wacom_led_groups_release,
+ wacom);
+ if (error)
+ return error;
+
+ wacom->led.groups = groups;
+
+ return 0;
+}
+
static int wacom_initialize_leds(struct wacom *wacom)
{
int error;
@@ -968,23 +1000,34 @@ static int wacom_initialize_leds(struct wacom *wacom)
case INTUOS4:
case INTUOS4WL:
case INTUOS4L:
- wacom->led.select[0] = 0;
- wacom->led.select[1] = 0;
wacom->led.llv = 10;
wacom->led.hlv = 20;
wacom->led.img_lum = 10;
+
+ error = wacom_led_groups_allocate(wacom, 1);
+ if (error) {
+ hid_err(wacom->hdev,
+ "cannot create leds err: %d\n", error);
+ return error;
+ }
+
error = wacom_devm_sysfs_create_group(wacom,
&intuos4_led_attr_group);
break;

case WACOM_24HD:
case WACOM_21UX2:
- wacom->led.select[0] = 0;
- wacom->led.select[1] = 0;
wacom->led.llv = 0;
wacom->led.hlv = 0;
wacom->led.img_lum = 0;

+ error = wacom_led_groups_allocate(wacom, 2);
+ if (error) {
+ hid_err(wacom->hdev,
+ "cannot create leds err: %d\n", error);
+ return error;
+ }
+
error = wacom_devm_sysfs_create_group(wacom,
&cintiq_led_attr_group);
break;
@@ -995,16 +1038,30 @@ static int wacom_initialize_leds(struct wacom *wacom)
case INTUOSPS:
case INTUOSPM:
case INTUOSPL:
- wacom->led.select[0] = 0;
- wacom->led.select[1] = 0;
wacom->led.llv = 32;
wacom->led.hlv = 0;
wacom->led.img_lum = 0;

+ error = wacom_led_groups_allocate(wacom, 1);
+ if (error) {
+ hid_err(wacom->hdev,
+ "cannot create leds err: %d\n", error);
+ return error;
+ }
+
error = wacom_devm_sysfs_create_group(wacom,
&intuos5_led_attr_group);
break;

+ case REMOTE:
+ error = wacom_led_groups_allocate(wacom, 5);
+ if (error) {
+ hid_err(wacom->hdev,
+ "cannot create leds err: %d\n", error);
+ return error;
+ }
+ return 0;
+
default:
return 0;
}
@@ -1204,7 +1261,7 @@ static ssize_t wacom_show_remote_mode(struct kobject *kobj,
struct wacom *wacom = hid_get_drvdata(hdev);
u8 mode;

- mode = wacom->led.select[index];
+ mode = wacom->led.groups[index].select;
if (mode >= 0 && mode < 3)
return snprintf(buf, PAGE_SIZE, "%d\n", mode);
else
@@ -1272,7 +1329,7 @@ void wacom_remote_destroy_attr_group(struct wacom *wacom, __u32 serial)
for (i = 0; i < WACOM_MAX_REMOTES; i++) {
if (wacom_wac->serial[i] == serial) {
wacom_wac->serial[i] = 0;
- wacom->led.select[i] = WACOM_STATUS_UNKNOWN;
+ wacom->led.groups[i].select = WACOM_STATUS_UNKNOWN;
if (wacom->remote_group[i].name) {
sysfs_remove_group(wacom->remote_dir,
&wacom->remote_group[i]);
@@ -1369,7 +1426,7 @@ static int wacom_initialize_remote(struct wacom *wacom)
}

for (i = 0; i < WACOM_MAX_REMOTES; i++) {
- wacom->led.select[i] = WACOM_STATUS_UNKNOWN;
+ wacom->led.groups[i].select = WACOM_STATUS_UNKNOWN;
wacom_wac->serial[i] = 0;
}

diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index 3e2c903..932d3ee 100644
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -808,7 +808,7 @@ static int wacom_remote_irq(struct wacom_wac *wacom_wac, size_t len)

for (i = 0; i < WACOM_MAX_REMOTES; i++) {
if (wacom_wac->serial[i] == serial)
- wacom->led.select[i] = touch_ring_mode;
+ wacom->led.groups[i].select = touch_ring_mode;
}

if (!wacom->battery &&
--
2.5.5